In a small saucepan over medium-low heat, melt the butter. Once melted, increase the heat to medium and let the butter begin to foam. Keep cooking and stirring with a spatula, until the butter begins to brown and gives off a nutty smell (2-3 minutes). Pour into a medium bowl and let cool completely
Add in the sugars, vanilla and salt to the butter mixture. Whisk to combine.
Add in the egg and egg yolk and whisk until smooth and glossy
Pour in the dry ingredients (the flour, baking powder, baking soda, kosher salt, cinnamon and nutmeg) and use a rubber spatula to combine until there are no more streaks of flour.
Add in your chocolate and butterscotch chips, but keep a small handful of chocolate and butterscotch to the side.
Scoop out the cookie dough using a 3 tablespoon ice cream scooper and place on a lined tray. Once finished, gently press the extra chocolate and butterscotch chips on top of the cookie dough balls – this will give you those puddles of chocolate! Chill for at least 30 minutes or up to overnight
Preheat your oven to 350°F/175°C and line 3 baking trays with parchment paper
Bake the cookies 6 at a time for 10-12 minutes.
Notes
My recipes have been developed and tested in metric grams. I highly recommend using a weighing scale and measuring out your ingredients the metric way. Butter: I use European style butter, like Kerry Gold, in my recipes. This will make your finished bake much creamier and richer.Salt: If you don’t have kosher salt, halve the amount of salt called for in the recipe. 1 teaspoon kosher salt = ½ teaspoon fine salt. Please note I am using Diamond Crystal Kosher Salt and not Morton Salt, which is a coarse kosher salt. Coarse kosher salt is much too salty for this recipe. Storage: keep the baked cookies in a tupperware for up to 1 week at room temperature. Freeze unbaked cookie dough balls for up to 2 months. When ready to bake, take them out of the freezer and bake at the same temperature as above but for an extra minute or two.